亚洲精品在线观看少妇,国产激情亚洲一区,国产人碰人摸人爱免费视频,久久国产精品一区二区,久久国产精品免费看,日韩欧美视频熟女,婷婷午夜电影在线观看,色婷婷国产麻豆精品,八年沉淀只做精品,国产在线视频专区,日韩欧美纯爱电视剧电影免费观看,亚洲国产日本免费观看,天堂亚洲欧美日韩一区二区,中文字幕有码系列在线观看,久久日韩精品一区,小明欧美精品视频在线观看,91av成人一区二区三区,欧美日韩亚洲综合在线一区二区,亚洲一区二区二三区日日骚,在线观看欧美一区二区三区精品,日本欧美黄色一级片,欧美av一区二区三区在线观看,91成人国产麻豆一区二区

Guangzhou Steel teach you: steel component manufacturing

Guangzhou Steel teach you: steel component manufacturing

Steel component manufacturing, transportation, installation, fire and rust.
(1) Manufacturing: steel manufacturing including loft, item number, cutting, correction and many other aspects.
(2) Welding: Welders must pass an examination and obtain a certificate in welding and must pass the examination within its project and its scope of accreditation. After welding seam welder stamp shall be marked in the weld process and site requirements. Guangzhou Steel